One of the things about looking at series from the past: It's good to remember the historical context.
There had been magical girls, before this. They transformed into pretty clothes and granted wishes (that generally went humorously wrong), or transformed into duplicates of their older sisters to find out if the boy that they had a crush on liked them. Pure Shoujo.
And there were superhero shows. Some of them even had a token female character that wasn't a stay-at-home love interest.
And then there was Sailor Moon, in which the clumsy, awkward girl who has hopeless crushes on the cute, unattainable guy teams up with her BFFs to blow the living crap out of demons with their magical powers.
Nobody else had done this before.
It was groundbreaking.
— "Unka Josh", RPGNet forums, 8/17/2009 (in the [In Which I Watch] Sailor Moon thread)